The present invention relates in general to surgical instruments, and, more particularly, to a sleeve apparatus for use in combination with a surgical instrument for removing a cataract through an incision in a patient's eye.
Cataracts, an opacity of the lens of the human eye, are commonly treated by performing a lensectomy, or cataract extraction, followed by replacement of the removed lens with an intraocular lens implant. Surgical instruments for performing a cataract extraction, such as phacoemulsification instruments, are well-known in the art, as shown by Banko et al, U.S. Pat. No. 3,589,363. These phacoemulsification instruments typically include a cutting tip, or needle. The needle is inserted through an incision in the patient's scleral/corneal junction in order to engage the lens. The needle is then caused to be vibrated, such as by ultrasonic vibrations, in order to emulsify the lens. As the lens is emulsified it is removed, by vacuum pressure, through a central bore within the cutting tip or needle. Inasmuch as a significant quantity of heat may be generated from the ultrasonic vibrations, a sleeve is commonly placed around a portion of the needle in order to preclude undesirable burning of tissue proximate the incision.
When performing a cataract extraction, as described above, it is desirous to preclude a loss of fluid from the eye, through leakage around the surgical instrument and through the incision, in order to preserve the eye's volumetric integrity, maintain intraocular pressure and maintain vital ocular structures. Accordingly, it is desirable to maintain a relatively tight seal between the surgical instrument and the incision, to preclude or reduce such loss of fluid. One prior art approach for maintaining this relatively tight seal is disclosed within Sorich, U.S. Pat. No. 4,515,583, which discloses an elliptical sleeve for a phacoemulsification instrument. The elliptical shape of this sleeve attempts to more closely approximate the configuration of the incision through the cornea.
While the elliptical sleeve disclosed within Sorich '583 may at times more closely approximate the incision's configuration, as compared to a fixed, circular sleeve, prior art sleeves such as those disclosed within Sorich '583 are relatively fixed in cross-sectional size, and may not be expanded or contracted in order to accommodate incisions of variable size and variable shape.
Accordingly, it is the object of the present invention to provide a sleeve apparatus for use in combination with a surgical instrument, wherein the sleeve apparatus is expansile in circumference in order to conform to incisions of a wide variety of shapes and sizes.
It is another object of the present invention to provide a method for removing a cataract through an incision in the patient's eye which includes expanding in circumference a surgical sleeve of a surgical instrument, in order to conform the sleeve to the size and shape of incision and/or interior of the wound in the patient's eye.
These and other objects, features, and modes of operation of the present invention will become apparent in light of the present specification, claims, and drawings.